Britain's demands from EU are not 'Mission Impossible': Cameron

LONDON (Reuters) - Prime Minister David Cameron will kick off his efforts to reform the European Union on Tuesday with a declaration that his demands are not "Mission Impossible", just the price EU leaders must pay if he is to keep Britain in the bloc.

Cameron, who has frustrated some EU officials by giving away few details on the changes he would like to see, will on Tuesday send a letter to the President of the European Council Donald Tusk, setting out his four main objectives.

Those are: guarantees of fairness for non euro zone members, greater competitiveness, exemption from the principle of "ever-closer union" and tackling freedom of movement abuses.

"There will be those who say, here and elsewhere in the EU, that we are embarked on Mission Impossible," Cameron will say in a speech in London, according to advance extracts released by his office. "I do not believe so for a minute."

The British leader has said he favors staying in a reformed EU but he will also use the speech to give his strongest warning yet that he might back Britain leaving the 28-member bloc unless other leaders agree to his demands.

The letter will mark the start of the renegotiation period before a December summit of EU leaders to hammer out the details of Britain's new terms. Cameron has promised a referendum on whether Britain should stay in the EU by the end of 2017.

"The European Union has a record of solving intractable problems. It can solve this one. Let us therefore resolve to do so," he will saying the letter.

Cameron has ramped up the case against those wanting to leave the EU in recent weeks, stressing the benefits of being in a reformed organization, after polls showed a narrowing gap between the "Yes" and "No" camps.

Opinion polls, however, still show that a majority of Britons favor staying within the bloc.